This is a new project for which the principal instrumentation, the Scanning Electron Beam Microprobe, will not be delivered until the next reporting period. The bulk of the work expended on this project to date has been in the evaluation and establishment of specifications of the instrument. The microprobe chosen is a Cameca MBX, 2-50MeV, two wavelength spectrometer machine. The expected delivery will be in January 1980. Preliminary electronic design of the computer interface has been accomplished. The principal investigator on this project has an extensive background in electron beam microanalysis applied to problems in materials science. He has been attending meetings and seminars germane to biological applications. Dr. Leroy, for this entire reporting period, has been on a training assignment in Orsay, France, acquiring the appropriate background in preparative techniques and in interpretation of results obtained by electron beam microanalysis.